From: Namjae Jeon linkinjeon@kernel.org
commit b096d97f47326b1e2dbdef1c91fab69ffda54d17 upstream.
ksmbd make a delay of 5 seconds on session setup to avoid dictionary attacks. But the 5 seconds delay can be bypassed by using asynchronous requests. This patch block all requests on current connection when making a delay on sesstion setup failure.
Cc: stable@vger.kernel.org Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-20482 Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ksmbd/smb2pdu.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
--- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -1874,8 +1874,11 @@ out_err: try_delay = true;
sess->state = SMB2_SESSION_EXPIRED; - if (try_delay) + if (try_delay) { + ksmbd_conn_set_need_reconnect(conn); ssleep(5); + ksmbd_conn_set_need_negotiate(conn); + } } }